Wow, too hard to pick one. But a few things come to mind in 30 seconds:-Season 2 "Man of Science, Man of Faith," starting with some guy riding a bike and listening to a record...suddenly, BOOM!!! WTF? HE'S IN THE HATCH??? SOMEONE LIVES IN THE HATCH???-Season 3 "A Tale of Two Cities", Otherville when we first meet Juliet, the book club, I'm wondering whose flashback this is, then suddenly they all run outside and we see the plane crash overhead. Ben, Goodwin, Ethan...WTF? THERE IS A VILLAGE ON THE ISLAND??-Season 6 "Dr. Linus" when Ben and Ilana were in the jungle and he was explaining himself. One of my favorite scenes ever.-The first time we "see" Smokey coming through the jungle...WTF IS THAT???-Michael dying, because my god, I was so looking forward to that.

Wow, too hard to pick one. But a few things come to mind in 30 seconds:-Season 2 "Man of Science, Man of Faith," starting with some guy riding a bike and listening to a record...suddenly, BOOM!!! WTF? HE'S IN THE HATCH??? SOMEONE LIVES IN THE HATCH???-Season 3 "A Tale of Two Cities", Otherville when we first meet Juliet, the book club, I'm wondering whose flashback this is, then suddenly they all run outside and we see the plane crash overhead. Ben, Goodwin, Ethan...WTF? THERE IS A VILLAGE ON THE ISLAND??

Those 2 really stand out for me also. The other one that as a huge WTF?!?! was the Season 3 Finale when Jack is at the airport, the car pulls up and out steps....Kate. Holy Snot!! WTF?!?! They got off the Island, and it's not a flashback it's a flash...forward. *brain explodes*

Favorite might be realizing that Kate and Jack were off island future at the airport.Loved the Juliet baking/bookclub scene and realizing they are on the island, plane crashing and that awesome pan out to show the whole Otherville and island. Jaw dropping moments like that.

I loved the scene at the beginning of There's No Place Like Home Part 1 when we see the Oceanic 6 and then the camera cuts out and we see the plane landing in Hawaii and they come out and are seeing their families for the first time. There was no dialogue, just music, and in slo-mo, and I was thinking that early on I would have thought that would have been the last scene of the series.

Absolutely loved that one - so many good scenes in there, and one that comes to mind is Charlie playing "Wonderwall" on the street in London, a mirror image to when he played it in front of Desmond during "Flashes Before Your Eyes." This was a great example of using the music to illustrate the theme of the episode.

The first visit to Othersville and Ben being left out of the bookclub - oh, yeah, and the whole plane breaking up thing!

And I'd like to add: the first time the timer ran down in the hatch and we saw the Egyptian symbols instead of numbers - I didn't know WTF was going to happen! I didn't know if they were going to implode, explode, or get transported to Egypt and find themselves inside a pyramid!